faraday

[Gadre] built his own ATtiny project without using any batteries. It’s an electronic Dice (or die if you’re being critical) which uses induction to charge a storage capacitor to act as the power source. The voltage generator is made from a tube of Perspex which houses a set of rare-earth magnets. At the enter of the tube [Gadre] machined a channel wich accepts about 1500 windings of 30 AWG magnet wire. When someone shakes the tube back and forth the magnet passes the wire, inducing a current. The product is stored in a 4700 uF capacitor, which feeds a boost converter to power the rest of the circuit.

The ATtiny13V that controls the circuit is running its internal RC oscillator at 128 kHz, the lowest setting possible in order to minimize power consumption. After a good shake the user can press a button to roll the die, which is then displayed for several seconds on a group of seven LEDs. See for yourself in the video after the break.

Have you ever wondered how they inspect high voltage cables without taking them out of service? Check out this video which offers a glimpse into the life of a professional high voltage cable inspector. There are parts of the job you’d expect—namely perching on the cable like a bird, trying to not fall off—but the part of the job you wouldn’t expect is the suit. This suit is made of 75% Nomex, to prevent it from catching fire, and 25% stainless steel thread, turning the suit into a wearable Faraday cage. Of course, because he’s got a Faraday cage mere millimeters from his skin, the cable inspector spends his workday surrounded by half a million volts. To avoid electric shock, he equalizes the voltage potential between himself and the line before touching the cable.